Clean Energy Fuels is the largest distributor of renewable natural gas (RNG) as a transportation fuel in the U.S. The company operates a network of over 600 fueling stations across 43 states, Canada, and Washington D.C., serving commercial fleet operators in refuse, public transit, airports, and heavy-duty trucking. RNG is biogas captured from dairy farms, livestock operations, and landfills — chemically identical to conventional natural gas but with a deeply negative carbon footprint. Clean Energy sources RNG from its own production facilities and from over 150 third-party suppliers, then dispenses it through its station network. Revenue comes from fuel sales and from Environmental Credits — federal RINs and state-level LCFS credits — generated when RNG is dispensed into vehicle fuel tanks. These credits are sold separately to obligated parties and represent a meaningful portion of Clean Energy's economics. Clean Energy also builds and maintains fueling stations for third-party fleets and sells LNG for marine, industrial, and other non-vehicle uses. The company is also building upstream dairy RNG production assets through joint ventures with bp and TotalEnergies, aiming to capture more of the full value chain. Clean Energy's central growth bet is heavy-duty Class 8 trucking, specifically adoption of the Cummins X15N natural gas engine, which was introduced in 2024 and is designed to match diesel for long-haul applications. Management views Clean Energy's station network — which it argues is larger than all competitors combined — as a structural advantage for both fleet customers and RNG suppliers seeking to maximize credit monetization.